Device for the continuous production of a strip of dough

ABSTRACT

The invention relates to a device for the continuous production of a strip ( 6 ) of dough from a mass ( 5 ) of dough, the width of said strip being a multiple of its thickness. The inventive device comprises at least one pair of opposite, interspaced, longitudinal guiding elements ( 8, 9 ) for guiding the dough. The dough passes through the gap ( 15 ) formed between the guiding elements and is guided by said guiding elements ( 8, 9 ), which are driven in opposing rotatory directions, from an intake end ( 16 ) of the device to an outlet end ( 17 ) of the same. At least one of the guiding elements ( 8, 9 ) is profiled on its circumference with a plurality of grooves ( 20 ) extending side by side, perpendicularly to the longitudinal direction of the respective guiding element ( 8, 9 ). Said grooves ( 20 ) assist the transport of the dough through the gap ( 15 ) and enable the bubbles in the dough ( 5 ) to be maintained.

The invention refers to an apparatus for continuous producing of a doughstrip, the width thereof is a multiple of its thickness, from a doughmass, with at least one pair of oppositely disposed elongated guidingelements for the dough, which guiding elements are formed by rollers andare adjustably spaced apart from each other, wherein the dough passesthrough the gap formed by this spacing and is guided by the rollersdriven in opposite direction of revolution from an intake end of theapparatus to an outlet end thereof, and wherein at least one of therollers is provided with a profile on its periphery, which profile isformed by a plurality of grooves extending side-by-side crosswise thelongitudinal direction of the respective roller, which grooves enhanceconveying the dough through the gap.

For producing of numerous bakery products it is necessary to transform adough mass supplied continuously or portion-wise, for example from akneader, into a continuous dough band, the thickness thereof as a ruleis small and amounts only a small fraction of the band-width. This doughband is then conveyed to further processing apparatus, for exampledevices, which cut the broad band into small strips, which are thenseparated from each other by spreading bands and are conveyed to formingapparatus of different kind. When forming this continuous dough band thedough must be treated carefully, so that baking products of satisfactoryquality are obtained. In particular, bubbles, in particular fermentationbubbles and air, present in the dough must be preserved and squeezing ofthe dough must be avoided.

An apparatus of the initially described kind is known from U.S. Pat. No.2,145,550 A for producing very thin dough sheets.

Further it is known from EP 744 126 B to provide on both sides of thegap a roller set each, the rollers thereof having a profile which isformed by a polygonal cross-section of the rollers. The latter apparatuscan indeed produce a dough band of substantially continuous thickness,however, it processes the dough not sufficiently careful, because theguiding elements delimiting the gap are moved periodically towards oraway from each other. When the oppositely disposed guiding elements getnearer to each other, the dough is squeezed and bubbles present in thedough can only to a limited extent evade to above or to below, and notat all within the initially described known apparatus.

The invention has at its object to improve an apparatus of the initiallydescribed kind so that the dough is processed more carefully and, inparticular, bubbles of different kind, present in the dough, arepreserved. The invention solves this task in that the gap is delimitedby two roller sets each one thereof having at least two rollers and thatthe width of the gap measured between oppositely disposed rollersdecreases from the intake end towards the outlet end, wherein therollers of each roller set have a circumferential speed that increasestowards the outlet end corresponding to narrowing of the gap and whereinon each roller set a flow-out of the dough between neighbouring rollersis avoided so that the grooves constitute an evading possibility forbubbles present in the dough, however keep the bubbles within the dough.This evading possibility exists at first in longitudinal direction ofthe gap, that is in direction from the intake end of the apparatus tothe outlet end thereof, but in addition thereto also side-wise, that isin longitudinal direction of the rollers, corresponding to the designingand the run of the grooves. It has been shown that thereby a particularcarefully dough band production is possible so that a dough band of highdough quality can be supplied to further dough processing. Thepossibility of adjusting the gap width enables one to extensively adaptto different qualities of the dough to be processed and thecircumferential speed of the rollers which increases towards the outletend of the gap avoids squeezing the dough caused by narrowing the gap.

A further advantage of the subject of the invention is that the periodicmotion of the rollers across to the longitudinal direction of the gap,present in the above mentioned known construction, is omitted, whatcontributes to simplifying the construction and thereby to saving ofcosts.

From EP 599 326 A1, indeed rollers acting onto the dough are known,which are provided with grooves extending perpendicularly to thelongitudinal direction of the rollers. However, these rollers are notdriven and they serve for producing a structure on the surface of thedough band. The rollers of the roller pair disposed at both sides of thedough band are so near each other disposed, that the profiles formed bythe grooves of the two rollers mate into each other like a toothing.Such a device does not allow an evading possibility for bubbles presentin the dough.

According to a preferred embodiment of the invention, the grooves extendparallel to each other or, respectively, closed in itself around theperiphery of the guiding element. A particular simple and clearlyarranged construction results, when the grooves extend perpendicular tothe longitudinal direction of the guiding element, however, alsothread-like extending grooves meet the initially described requirements.

According to a further embodiment of the invention slots can be providedin at least some of the projections existing between neighbouringgrooves, the direction of the slots crossing the direction of thegrooves. These slots constitute an additional free space for evading ofgas-bubbles and in addition they avoid that the dough slides through inlongitudinal direction of the gap when this longitudinal directionextends obliquely or vertically.

Although in the most cases the gap will so disposed that its axisextends vertically, the invention is not limited thereto, on thecontrary, the gap can extend obliquely or horizontally from the intakeend towards the outlet end.

The rollers may have different profiles and, respectively, or groovesand, respectively, or sizes and the guiding elements can be elements ofdevices which apply substances onto the dough, for example oil, aflouring, a dusting and the like.

Further features and advantages of the invention result from thedescription of exemplative embodiments schematically shown in thedrawings.

FIG. 1 shows a first exemplative embodiment of the invention in alongitudinal section.

FIG. 2 shows an embodiment in which the supplied dough strand is coveredwith flour.

FIG. 3 shows the adjustment of the width of a roller gap, which isdelimited by two roller sets.

FIGS. 4 and 5 show variants to the embodiment of FIG. 3.

FIG. 6 shows the shape of the grooves on a roller.

FIG. 7 shows a variant to the embodiment of FIG. 6.

FIGS. 8 and 10 show further embodiment variants, and the

FIGS. 9 and 11 are sections taken along the lines IX to IX of FIG. 8 orXI to XI of FIG. 10, respectively.

FIG. 12 shows in an enlarged scale a section taken along the line XII toXII of FIG. 1.

FIG. 13 shows in a section taken along the line XIII to XIII of FIG. 1an embodiment variant.

FIG. 14 is a variant of the embodiment of FIG. 13 with mating rollergrooves.

FIG. 15 shows an embodiment for driving the rollers with differentrevolution speeds.

FIGS. 16 and 17 show embodiment variants having an obliquely directedor, respectively, substantially horizontally extending roller gap.

FIG. 18 shows in a section an embodiment having strippers related to therollers.

FIG. 19 shows an embodiment having oiled rollers.

According to the embodiment of FIG. 1, the apparatus has a framework 1having on top a hopper 2 for filling in the dough to be processed.According to this embodiment, this dough is supplied in form of doughportions 4 by means of a conveyor belt 3. Within the hopper 2, thesedough portions 4 form a dough mass 5 from which a thin dough strip 6 isformed, which is laid down onto a conveying-off belt 7 and is conveyedoff by this conveyor belt 7 in direction of the arrow 40. Transformingof the dough mass 5 in a thin dough strip 6 is made by two sets ofguiding elements 8, 9. Each guiding element set is formed by fourelongated rollers 10, which are bearingly supported for rotation withparallel axes 11 on two side walls 12 of the framework 1 which aredisposed at the front ends of the rollers 10. These rollers 10 form adough strip 6 having a width that is a multiple of its thickness. Therollers 10 of each guiding element set are driven in the same direction,however for the two guiding roller sets oppositely in direction of thearrows 13, 14. All rollers 10 of the two sets of guiding elements 8, 9are of the same size, however having so disposed axes 11 that the gap 15between two opposite rollers 10 narrows from the intake end 16 of thetwo guiding element sets 8, 9 towards the outlet end 17 like a hopper,however, the width of the processed dough strip 6, when measured indirection of the axes 11 of the rollers 10 remains constant. By the saidrotation of the rollers 10 in direction of the arrows 13 or 14 the doughis conveyed through the gap 15 in direction of the arrow 18. Thisconveying is assisted by providing the rollers on their periphery with aprofile 19 (FIG. 6) which is formed by a plurality of grooves 20extending side-by-side crosswise the longitudinal direction, that meansacross the direction of the axes 11 of the rollers 10. Within theembodiment of FIG. 6, these grooves 20 extend parallel to each otheraround the periphery of the roller 10 in form of closed rings disposedin planes extending perpendicularly to the axis 11 of the roller 10.These grooves constitute at the same time a space into which bubbles offermentation gases or air present in the processed dough mass 5 canevade, which bubbles should be preserved in the sense of a high doughquality. Therefore, squeezing of the dough and destroying of thesegas-bubbles is avoided. The evading spaces formed by the grooves 20allow as well a side-wise evading of the gas-bubbles in direction of theaxis 11 of the rollers 10, therefore, from the projections 1 delimitingthe grooves 20 into the hollow spaces formed by the grooves 20, as anevading possibility in longitudinal direction of the gap 15, thereforein conveying direction 18 of the dough or opposite thereto, thereforealong the ring-shaped hollow spaces formed by the grooves 20.

However, the grooves must not extend in planes disposed perpendicularlyto the axis 11. As FIG. 7 shows also a thread-like arrangement of thegrooves 20 is possible and is efficient in the sense of the invention.

A further assistance of the conveying action of the rollers 10 onto thedough 5 can be obtained by providing at least some of the projections 21existing between neighbouring grooves 20 with slots 22 (FIG. 8)extending parallel to the axis 11 or also obliquely thereto. These slots22 form the periphery of the projections 21 like a knurling by which thesaid additional conveying action is assisted and it is avoided that thedough slides between the rollers 10 in direction of the arrow 18.

As a rule, however, not compulsory, the rollers 10 of each set are sodisposed that they just contact each other with their outermostperiphery portions (FIG. 1). Thereby, a flow-out of the dough 5 betweenrollers 10 neighbouring each other is avoided. However, from thisengaging arrangement is swerved, if the profile of the rollers 10 is notcircular, and FIGS. 10 and 11 show an embodiment for this in which theprojections 21 are also provided with slots 22 extending crosswise theperipheral direction. This embodiment shows a hexagonal cross-section ofthe projections 21, when seen in direction of the axis 11. Othersuitable shapes of the cross-section are possible, in particularpolygonal cross-sections having more than six sides or ovalcross-sections. In the latter, a periodic narrowing or enlarging of thegap 15 existing between opposite rollers 10 occurs, when the axes 11 ofthe opposite rollers 10 are fixly bearingly supported and both opposingrollers 10 revolve with the same speed, are of the same size and thehills and dales of the oval roller cross-section meet each other. Thiscould result in a periodic squeezing of the dough. In order to avoidthis for an oval roller cross-section, the rotation of the rollers 10can be so chosen that always a dale of the oval roller cross-section ofthe one roller 10 neighbours the gap 15, when for the other roller 10the hill of the oval roller cross-section neighbours the gap 15. In sucha manner an at least substantially constant width of the gap 15 betweenthe two opposing rollers 10 can be ensured.

Supplying the dough to be processed must not be made in form of doughlumps 4, as this is shown in FIG. 1. However, it is possible to supplythe dough to be processed in form of an already pre-formed dough sheet23 (FIG. 19). The width of the gap 15 is adjustable in order to enableone to adapt to different dough qualities. For this, the axis 11 of theone roller 10 of the roller pair may be bearingly supported in crosspieces which are slideably disposed relative to the framework 1, aneccentric drive 26 being provided for this sliding and therefore for anadjustment of the gap. Such an adjustment of the effective width of thegap 15, of course, can also be made for sets of opposite rollers 8, 9.FIG. 3 shows an embodiment in which the hopper-shaped extending gap 15is delimited by four pairs of rollers 10. The rollers 10 of the rightguiding element set 9 are bearingly supported with their axes 11 onplates 27, and the plates are swivelable around the uppermost axis 11relative to the framework 1. The adjustment is made by means of aneccentric drive 26.

FIG. 4 shows an embodiment variant for this, wherein only the lowermostroller 10 of the right roller set is adjustable for adjusting the widthof the gap 15.

Whereas FIGS. 3 and 4 show an adjustment of the eccentric drive 26 byhand, by means of a hand lever 28, within the embodiment according toFIG. 5 a motor 29 is provided for adjustment of the eccentric drive 26,which motor is controlled in a suitable manner. Such a motor, of course,can be provided for each kind of the adjustment of the roller gap.

FIGS. 6 and 7 show a rounded profile of the projections 21, thisprofile, however, can also be flattened, as the section according toFIG. 12 shows. Further, the rollers of the guiding element sets 8, 9and/or the rollers 10 being opposite with respect to the gap 15 must notbe equal to each other, however, also rollers of different design can becombined with each other, in particular rollers of different diameters.

Further, it is also possible, as FIG. 13 shows, to dispose the grooves20 of neighbouring rollers 10 displaced in direction of the roller axes11, and within each embodiment different roller shapes can be combinedwith each other.

As FIG. 14 shows, the grooves 20 of neighbouring rollers 10 of a set 8or 9 can be so constructed and the several axes 11 of neighbouringrollers 10 of this set can be disposed so near each other that thereresults a mating disposition of the grooves 20 or the projections 21delimiting them. Thereby, also a self-cleaning of the rollers 10 isobtained.

Driving the rollers 10 for rotation can be obtained from a common motorby means of suitable gearings. FIG. 15, however, shows an embodimentvariant in which an own motor 29 or 30 is provided for each one of thetwo roller sets 8, 9. Each motor 29 or 30 drives a drive chain wheel 31from which chains 32 lead to drive pinions 33, 34, connected for commonrotation with the axes 11 of the several rollers 10. This enables one ina simple manner to drive the several rollers of each roller set 8 or 9with different revolution speed. For this, it is sufficient to give thedriving pinions 33, 34 a different size. Suitably, the arrangement is sochosen, that the revolution speed of the 15 rollers 10 increases fromthe intake end 16 of the gap 15 towards its outlet end 17, and thiscorresponding to the narrowing of the cross-section of the gap 15. Ifdesired, opposite rollers 10 can also have different revolution speeds.

In FIG. 15 the arrangement is so chosen, that the revolution speed ofthe rollers 10 of each roller set 8 or 9 increases stepwisely from up todown. However, the arrangement can also be so chosen, that, for example,the two uppermost drive pinions 33 of each roller set are of the samesize and also the two lowermost drive pinions 34, wherein, however, thelatter are smaller than the drive pinions 33. In such a manner a coarsestepwise increase of the revolution speed is obtained from up to down.

The apparatus must not be so constructed that the gap 15 remainingbetween the roller sets 8, 9 extends vertically or nearly vertical.However, it is possible to give this gap 15 also an inclined axis, asthis is shown in FIG. 16. Also a construction according to FIG. 17 ispossible, in which the intake end 16 and the outlet end 17 of the gap 15have nearly or completely the same level. In such an embodiment, thedough to be processed is suitably supplied by means of a conveyor belt3, whereas within the embodiment according to FIG. 16 also supplying bymeans of a hopper 2 is possible.

A stripper 35 (FIG. 18) each may be assigned to the opposing rollers 10,the edge thereof neighbouring the respective roller 10 is formedcorresponding to the shape of the grooves, so that the stripper 35meshes like a toothing with the projections 21 of the grooves 20 of theroller 10. If disposed obliquely and loaded with flour 36, thesestrippers 35 may also form a member of a flouring device for the groovedrollers 10.

Similar constructed strippers 35 are shown in the embodiment accordingto FIG. 19, wherein always a stripper 35 is related to one of therollers 10 of each one of the roller sets 8 or 9. A drop oiler 37 isrelated to each one of the strippers 35, which applies oil dropwisely onthe stripper 35, wherefrom the oil flows to the neighbouring roller 10.In such a manner oiling of the rollers 10 or, respectively, of the doughconducted by them, is possible.

Instead by means of strippers 35, oiling the dough can also be made bymeans of distributor rollers or brushes.

FIG. 2 shows an embodiment in which the supplied pre-formed dough strand23 is dusted from above and from below, two dusting devices 38, 39 areprovided for this. The dusting device 38 applies flour to the surface ofthe dough sheet 23, that lies already on the conveyor belt 3, whereasthe dusting device 39 applies flour on the conveyor belt 3 alreadybefore the dough strip 23 is put onto the conveyor belt. In such amanner a dough strand 23 that is floured on both sides, flows on theintake end 16 of the gap 15 existing between the two roller sets 8, 9into the gap in direction of the arrow 18. Putting-off of the doughstrip 6 that has received the desired shape by the lowermost roller pair10 is made continuously onto a continuously revolving conveying-offbelt, which moves in direction of the arrow 40. By dusting the supplieddough sheet 23 on both sides, it is avoided that the soft dough adheresto the rollers 10.

In a similar manner, also an oiling device can be constructed instead ofa dusting device.

1. Apparatus for continuous producing of a dough strip (6), the widththereof is a multiple of its thickness, from a dough mass (5), with atleast one pair of oppositely disposed elongated guiding elements (8, 9)for the dough, which guiding elements are formed by rollers (10) and areadjustably spaced apart from each other, wherein the dough passesthrough the gap (15) formed by this spacing, which gap (15) is delimitedby the at least one pair of guidling elements, each guiding elementhaving at least two rollers (10), so that the dough is guided by therollers (10) driven in opposite direction of revolution from an intakeend (16) of the apparatus to an outlet end (17) thereof, and wherein thewidth of the gap, when measured between oppositely disposed rollers(10), decreases from the intake end (16) towards the outlet end (17),and at least one of the rollers (10) is provided with a profile (19) onits periphery, which profile is formed by a plurality of grooves (20)extending side-by-side crosswise the longitudinal direction of therespective roller (10), which grooves enhance conveying the doughthrough the gap, characterized in that the rollers (10) of each rollerset (8, 9) have a circumferential speed that increases in correspondenceto narrowing of the gap towards the outlet end (17) and that the atleast one roller is provided with the profile (19), so that the grooves(20) constitute an evading possibility for bubbles present in the dough(5), however keep the bubbles within the dough.
 2. Apparatus accordingto claim 1, characterized in that the grooves (20) extend parallel toeach other.
 3. Apparatus according to claim 1, characterized in that thegrooves (20) extend closed around the periphery of the roller (10). 4.Apparatus according to claim 3, characterized in that the grooves (20)extend perpendicularly to the longitudinal direction of the roller (10).5. Apparatus according to claim 1, characterized in that the grooves(20) extend helically.
 6. Apparatus according to claim 1, characterizedin that slots (22) are provided in at least some of the projections (21)which exist between neighbouring grooves (20), the direction thereofcrosses the direction of the grooves (20).
 7. Apparatus according toclaim 1, characterized in that the width of the gap (15) is adjustableonly over a part of its length measured from the intake end (16) towardsthe outlet end (17).
 8. Apparatus according to claim 1, characterized inthat an eccentric drive (26) and/or at least one motor-driven adjustmentdevice (29, 30) is provided for adjusting the width of the gap. 9.Apparatus according to claim 1, characterized in that the gap (15)extends obliquely or horizontally from the intake end (16) towards theoutlet end (17).
 10. Apparatus according to claim 1, characterized inthat the rollers (10) have different profiles and/or different groovesand/or different sizes.
 11. Apparatus according to claim 1,characterized in that the grooves (20) of the rollers (10) of theguiding elements (8, 9) neighbouring each other are offset with respectto each other.
 12. Apparatus according to claim 11, characterized inthat for rollers (10) neighbouring each other, the projections (21)defining the grooves (20) mate with each other.
 13. Apparatus accordingto claim 1, characterized in that a stripper (35) is assigned to the atleast one roller (10), which stripper constitutes a member of a devicefor flouring, dusting or oiling and preferably mates with the grooves(20) of the at least one roller (10).
 14. Apparatus according to claim1, characterized in that the at least one roller (10) constitutes amember of a device for flouring, dusting or oiling.
 15. Apparatusaccording to claim 9, characterized in that a flow-out of the doughbetween rollers (10) neighbouring each other is avoided by the fact thatthe rollers (10) contact each other with their outermost peripheralparts.